LABORATORY ASSESSMENT OF THE EFFICACY OF A FABRIC TO CONTROL HOUSE DUST MITES

Transcription

1 LABORATORY ASSESSMENT OF THE EFFICACY OF A FABRIC TO CONTROL HOUSE DUST MITES SAMPLE: sample received 31 st July 2017 SPONSOR: SmartfiberAG Im Weidig 12 D Rudolstadt GERMANY SEPTEMBER 2017 Report # 2255/0917R 1

2 GOOD PRACTICES STUDY TEC N : SPONSOR: 2255/0917 Smartfiber AG (Germany) PRODUCT: Sample received 31st July 2017 FACILITIES: DATES: REPLICATES: STUDY DIRECTOR: STUDY ENGINEE: QUALITY RESPONSIBLE: T.E.C. 1, rue Jules Védrines, ZAC Maignon Anglet - France 03/08/2017 to 14/09/ Bruno Serrano / ENSAT engineer Martine Falquier / ENSAR engineer Bruno Serrano / ENSAT engineer METHODOLOGY: This trial has used a methodology adapted from the standard NF G which is in the appendix of the proposed methods for biocide registration in the «Guidance on the Biocidal Products Regulation - Volume II Efficacy Assessment and Evaluation (Parts B&C) Version February ECHA». ARCHIVING: DIFFICULTIES/DEVIATIONS: 10 years, hard + electronic copies None Bruno Serrano Date: 20 th September

3 PARTICIPANTS TO THE TRIAL Bruno SERRANO Trial responsible / T.E.C. Director Agronomist engineer ENSAT T84 Martine FALQUIER Trial enginneer Agronomist engineer ENSAR R74 Marie-Paule MONTAUT Technician Internal formation Adeline D'ANGELO Metrology responsible Master chemist Warning The results described in this report are produced by a laboratory test on the samples provided which have not suffered any damage related to the reality of use or of storage. TEC provides test results only on samples received and may in no event be liable regarding finished products in production or sale. The trial has been conducted on a laboratory strain of model insects and the susceptibility of the local insect s strains can be different in other labs or in the real conditions of use. As such the results should be taken only as an indication of the potential for activity of the formulations or products under test. Then, these results cannot be considered as confirmation that a formulation or product will work in a clinical or field application. Evidence for such activity can only be obtained from properly constructed and executed clinical or local field trials. Test variability on bioassays implies that the results of test given by TEC shall only be taken as one of the elements that contribute to the development of a product, but cannot be the sole support of product knowledge leading to its production and marketing/sale, and TEC strongly encourages the client to carry out further studies to consolidate the knowledge of the product's effectiveness. 3

4 LABORATORY ASSESSMENT OF EFFICACY OF A FABRIC TREATMENT TO CONTROL HOUSE DUST MITES 1. PURPOSE The purpose of this study was to assess the effect of an impregnating treatment of fabric on the development of house dust mites populations (Dermatophagoides pteronyssinus) in comparison with a population no exposed to the product. The trial was done by deposit of dust mites on the fabrics impregnated or not with the active specialities. Trial duration was 6 weeks, which corresponds to 2 development cycles of the mites. 2. MATERIALS AND METHOD The methodology was adapted from the standard AFNOR NF G Deviations from the standard: 2.1. Mites strain preparation Mites used were Dermatophagoides pteronyssinus strain originated from a stock culture of I.N.R.A. Bordeaux (France). It was a susceptible strain reared at 25 C and 76%RH for several years in laboratory conditions without any contact with insecticides on a oligidic diet of wheat germ (dried and powdered) and of brown brewers yeast (Prolabo, debittered, dried and powdered) (1/1 w/w). The mites were retrieved from the surface of the rearing medium where the mite colony is generally concentrated Number of mites 50+/-5 adult mites of mixed sex were used per experimental unit Food source The food source type I was used Mortality assessment procedure The assessment of mite s survival was done using the Heating Escape Method with low temperatures (30 to 40 C) (Bischoff). Data will show the compared population s evolution between the Treated and the Untreated during the 2 cycles of development. Calculation of efficacy is explained on Replicates, Control 4 replicates were conducted the same day, including for the untreated fabric which was the Control. 3. TEST SAMPLE Experimental sample (received the 31 st July 2017). 4

5 4. RESULTS 4.1. Presentation Data are numbers of alive mites. As it is a comparison between Treated and Untreated batches, the calculation of efficacy was done with the: POPULATION CONTROL COEFFICIENT = CP CP = mites alive in Untreated - mites alive in Treated x 100 mites alive in Untreated This data is the product efficacy coefficient. - the closer to 0 the coefficient will be, the less efficient the treatment will be because the population will develop at the same rate as for the untreated; - the closer to 100 the coefficient will be, the more efficient the treatment will be by killing the dust mites population and stopping its expansion process. The table next page gives the raw data of the different experimental units Comments The natural evolution of mites population in Untreated batches ratifies the trial as it confirms the extremely favourable conditions under which the batches are tested: the population on the untreated batches have indeed a development factor more than 18 (more than 900 mites obtained from the original 50). Result on the efficacy of the sample: 62% population reduction. 5. CONCLUSION In the conditions of this trial, with the sample provided, the mites strain and the methodology used: The sample has proved an 62% control of the house dust mite s populations. 5

6 RAW DATA POPULATION'S REDUCTIONS after 6 weeks Replicate A %reduction Untreated control Mean 893,5 - sd 19,5 - Test sample , , , Mean sd 1,7 A = alive 6